Spot lights that illuminant a person or a certain area of a stage are commonly known within the entertainment industry. Such spot lights typical comprise a light source creating a beam of light that is used to create various optical effects. The light source is integrated into an optical system which typical comprises a number of optical elements, such as reflectors, color filters, dimmers, lenses, beam shaping elements etc., for forming the light beam. Some of these optical elements can typical be adjusted manual by a person whereby the appearance of the light beam can be change changed.
Spot lights are often used as follow spots by mounting a spot light on an arrangement allowing the spot light to be paned and tilted. The follow spot can thus be manual panned and tilted and moving objects can thereby be followed by the light beam.
Intelligent light fixtures like moving head comprise also a light source and optical elements generating a light beam. The operation of the light source and optical elements has been automated as known in the art and such moving heads are typical electronically coupled to the light controller that can control a large number of moving heads. A light show can be programmed on the light controller and the light controller will automatically send control signals to the moving heads.
Moving heads is also used as follow spots following a moving person on a stage, but these moving heads need to be programmed at the lighting controller in order to move. The moving head will thus move in a predetermined pattern and the person/artist thus need to move in the same pattern as the moving head to be in the spot light. However many artists often improvise his/her way of moving or forgets the predetermined moving pattern and the person will as a consequence not be correct illuminated by the follow spot.
A light show therefore often comprises both manual follow spots which are only used when the follow spot function is needed and a number of moving heads which are only used in the preprogrammed light show. This is both expensive and takes a lot of space in connection with the show. Further it is often necessary to have more than one spot light following the same artist which thus needs many persons manually operating the manual follow spots. It has previous been attempted to construct several full automated follow spot systems, where the moving heads automatic follows an artists but none of these systems have been able to function properly.
U.S. Pat. No. 6,866,402B discloses a multi parameter lighting fixture, which includes a locking system for pan and/or tilt, either of which may include a manual input device and an actuator. The locking systems for pan and tilt can be manually locked or unlocked by a technician using their respective manual input devices and automatically locked or unlocked by their respective actuators. A yoke of the multi parameter lighting fixture can be locked in more than one rotational position in relation to the base housing. In addition, the lamp housing of the multi parameter lighting fixture can be locked in more that one rotational position in relation to the yoke. The locking systems for pan or tilt can be automatically locked by an appropriate actuator in response to an electronic control system.
EP1001212 discloses an automated lighting fixture which automatically locks specific moving part(s) into fixed position(s) when power is not supplied to facilitate packaging, shipping, load-in and load-out of the fixtures. These light fixtures is locked into fixed positions in order to maintain a fixed position during transportation, storage or repair and can not be used as follow spots and are the light source ore further turned off when locked in these fixed positions.
JP9063303 discloses a master spotlight that is, remotely operated and is swing-driven, the master spotlight detects a drive angle by a swing drive, and outputs the same to a controller unit as a position detection signal. Based on the position detection signal, the unit outputs drive control signals to slave spotlights. Based on the drive control signals, the slave spotlight drive control portions control the swing drives so that the spotlight radiation directions follow the radiation direction of the master spotlight